Right angle drafting triangle



9, 1955 H. F. ACKERMANN, JR 3,264,733

RIGHT ANGLE DRAFTING TRIANGLE Filed Feb. 4, 1964 2 Sheets-Sheet 1 1 r 2lNVENTOR HERMAN/V F. AckERMAA/N, L/R.

BY MyP ATTORNEY z g- 9, 1956 H. F. ACKERMANN, JR 3,264,738

RIGHT ANGLE DRAFTING TRIANGLE Filed Feb. '4. 1964 2 Sheets-Sheet 2INVENTOR HERMAN/V F. AckERMA/v/v, JR.

BY HX PM ATTORNEY United States Patent 3,264,738 RIGHT ANGLE DRAFTINGTRIANGLE Hermann F. Ackermann, In, 3900 Greystone Ave, Riverdale, N.Y.Filed Feb. 4, 1964, Ser. No. 342,371 7 Claims. (Cl. 33-108) Thisinvention relates to a 45 degree right angle triangle. Moreparticularly, it relates to conventional 45 degree right angle draftingtriangles.

Heretofore, a considerable amount of drafting was done within arelatively small area on the drawing board. This is so especially incases involving detailed drawings, wherein there is a great amount ofshifting of drafting instruments and consequent moving back and forth ofthe T-square or parallel edge used in such drafting oper-a tions orprocedures. This would entail additional expenditure of time and effort.

The conventional 45 degree right angle triangle is easily manipulatedfor drawing right angle and 45 degree angle lines along the edges of thetriangle when used in conjunction w-ith the straight edge of theT-square or a parallel edge. Also, other horizontal or parallel linesare commonly drawn along the straight edge of the T-square or paralleledge. This procedure requires changing or shifting from the T-square orparallel edge to the triangle and vice versa. When having to draw manyhorizontal or parallel lines along the straight edge of the T-square orparallel edge, the T-square or parallel edge has to slide over the wholewidth of the drawing board.

In order to obviate the above undesirable features, it is an object ofthis invention to provide 45 degree right angle triangle having anattachment with a straight edge that can be readily and easily used inconjunction with said drafting triangle, for executing lines that areparallel with the base of the triangle without having always to use theT-square or parallel edge for that purpose.

With my invention hereinafter fully described and illustrated, aT-square or parallel edge can be kept, more often, in one position on adrawing board and used as usual for sliding the base of the triangleagainst, and drawing all lines that are at a right angle and all linesthat are at a 45 degree angle, to the straight edge of the T-square orparallel edge. In such case most lines that are drawn parallel to thebase of the triangle can be drawn along the straight edge of the abovementioned attachment.

Still another object of my invention is to provide in a right angletriangle a scale, that is marked off preferably in inches andsub-divisions of the inch, although other units of measurement may bemade,- for the desired and accurate spacing of any parallel lines thatare executed along the straight edge of the attachment.

Furthermore, the attachment forming part of this invention has aslidable, pivotal hinge movement for swinging the attachment to a flatand fixed position on the top face of the 45 degree right angletriangle, so as to use the triangle as customary when the attachment isnot in use.

Other features and advantages of the invention will be readilyappreciated as the same becomes better understood by reference to thefollowing detailed description taken in conjunction with theaccompanying drawings, in which:

FIGURE 1 is a .plan view of the preferred embodiment of the inventionwith a movable attachment in a closed position disposed on top of a 45degree right angle drafting triangle.

FIGURE 2 is a plan view similar to FIGURE 1 of the invention, butshowing the attachment in an open extended position and ready for use.

FIGURE 3 is an exploded, detail, and cut-away perspective view of thevarious parts comprising the invention, and

"ice

FIGURE 4 is a fragmental, partly broken away view in perspective of amodified form of the attachment embodying the invention. a

Referring now to the drawings, wherein like reference numerals designatelike or corresponding parts throughout the several views, there is shownin FIGURES 1 and 2 a conventional 45 degree right angle draftingtriangle 10 with various modifications.

The triangle made of any suitable material is provided with anattachment 10a which comprises a flat and preferably transparent arm 11,with a straight edge 12 extending out an angle of 45 degrees from thehypotenuse edge 17 of said triangle 10. When said attachment 10a is inan open position, as shown in FIGURE 2, straight edge 12 will beparallel with the base of the triangle 10. Arm 11 is fastened by meansof rivet or screw members 13, to the supporting underside of a bracket14, the long end of said bracket having parallel edges extendingoutwardly parallel with edge 12, over a portion of the top face of thearm 11. The other end of said bracket 14 tapers to a wider width,jointly and integrally, to form a bearing 15 which is bored centrally orthe end is turned over itself to fit and slide evenly on a rod 16. Saidrod 16 is held in a fixed position, with the axis of said rod beingparallel to the hypotenuse edge 17 of the triangle 10. Rod 16 isinserted at both ends in bearings 18 and 19, which are bored to fit orhold both ends of the rod 16. The bearings 18 and 19 are integrallyconnected to flanges 20, and have holes 21 in said flanges for rivetingor screwing said flanges securely to the top face of hypotenuse edge 17.It will be noted that said flange are disposed near the two apices thatform the hypotenuse of the triangle 10, thus holding the rod 16 in afirmly fixed position over the top face of the triangle 10 and parallelwith edge 17.

In FIGURE 1, it will be noted that the attachment 10a is shown in aclosed position and lying flat on the top face of the 45 degree rightangle triangle 10, and that straight edge 12 is now parallel with edge22 of the triangle, said edge 12 being perpendicular to the base leg 22aof the triangle.

On rod 16, between one end of the bearing 15 and the end of the bearing18, there is provided a compression spring 23. In its closed position,the free end of the arm 11 meets a strike 24 secured to the top face ofthe triangle 10 and near the apex of the degree angle of said triangle.The tension created by spring 23, serves to keep the attachment in aclosed position between the rod 16 and the strike 24. Said strike 24 israbbeted where it meets the free end of the arm 11. The free end of thearm 11 is provided with a lip 25 that fits into the rabbeted part of thestrike 24, thus holding said attachment in a locked position whendesired.

Attachment 10a is released by pressing the bearing 15 against the spring23 and in the direction of the bearing 18, thus releasing the lip 25from the rabbeted strike 24. It will be noted that bearing 15 is bored,the axis of said bore being at a 45 degree angle to the straight edge12, so as to pivot centrally on the rod 16. Thus said attachment isrevolved from the closed position to lay flat and on the same plane withthe triangle 10. Straight edge 12 of the arm 11 is then parallel withthe base 22a of the triangle 10, see FIGURE 2.

A pointer 26, forming part of bracket 14, is provided with the edge ofsaid pointer being parallel with edge 12 of arm 11. Said edge is locatednear the bearing 15, to ride over the top face of the triangle, adjacentand parallel with hypotenuse edge 17. The top face of the triangle isprovided with scale lines 27 engraved thereon. Said lines are providednear hypotenuse edge 17 to be under the pointer 26. Lines 27 areparallel with the edge of the pointer 26, said lines being divided intoinches andsub-divisions of the inch or of any desirable unit ofmeasurement such as centimeters and millimeters. Pointer 26.may bereadily brought into registry .with 'a selected scale line 27 formeasuring the desired distance between any paralel lines thatareexecuted along straight edge'12 of arm 11.

Referringnow to FIGURE 3,-further details show more fully the same andother features of the preferred invention in FIGURES 1 and 2, whereinthere is provided.

an open slot 28. Said slot 28 hastwo long sides 30 running parallel withthe hypotenuse edge or side 17 of the 45 degree right angle triangle 10.Also, said slot is equal and.

continual in profile along its full length and is located midway betweenthe hypotenuse edge 17 and the opposite edge, from edge 17, therebyforming a triangular cut-out 29; Slot 28 terminates, at both ends,slightly short of the two apices that form the hypotenuse side of'thetriangle10, the ends of said slot being cut at right angles to the longsides of slot 28. The long sides of slot 28.

'are concave in profile along their full length; and near thetop side ofthe triangle 10. The concave sides. 30

have an arc radius equal to the outside radius of the bearing 15,whereby the concave sidesfitl form a continual recess, atthe top side oftriangle 10, to permit parallel slidable movement of the bearing insaidgconcave recessed sides 30.

Bearings Hand 19. are. bored centrally and are on, the same axis. Also,they'have a radius equal to' the;

other Flanges .20 are provided with openings ,or holes 21. to receiverivets or screws 31 forv fastening. said flanges 20 tothe top face ofthe triangle. 10, thereby holding the bearings IS-and 19 in a fixedposition, with the underside of said bearings resting in the concavesides 30 .at the extreme endsfof slot 28.

Triangle-10 is also provided with holes 32,"bored to be in directrelation to the flange holes 21, and are of the same size to jointlyreceive the rivets ,or screws31, for fastening said flanges, 20to thetop face of the triangle 10, as above explained. Rivets or screws 31being countersunk on the. underside of the triangle 10, leave noprotrusions on the underside of. said triangle. The bores inthe'bearings 18 and 19 receive a suflicient portion of the extreme endsof the rod 16 to reta'm said rod. Bores -in the bearings 18 and 19 stopon the inside to abut the fiat ends of rod 16, thus holding said rod inafixed position, wherein the axis of said rod 16 willbe parallel with thehypotenuse edge 17 of thetriangle. Rod 16 is inserted in the constantdiameter of the'bore in the bearing 15, thus placing the bearing 15in aposition for slidable and parallel movement in the concave recessed slot28, along the hypotenuse side of the triangle 10, as previouslyv the topside of the triangle 10, means being providedto fasten the extended endof the bracket 14 to a sufiicient portion of the top side ofthe armll.Said means" are holes 33 through the extended end of the bracket 14 soas to line up with-holes 34 through the arm 11. Said 1 the underside ofthe bracket 14. Rivets or'screws 13 are countersunk, to leave noprotrusions of the same on the top face of theextended end of thebracket 14 nor on the underside of. the straight edge. arm.11.

With the attachment in its open position on a drawing surface, theundersideof the arm;11 will be on the same plane asthe underside of thetriangle 10,2 and the straight edge 12,.will be at a 45 degree angle .tothe triangle edge 17, makingsaid straight edge 12 parallel with the baseof the triangle 10. Thus the straight edge '12 meets the. edge 35 at-a'45 degree angle so that the edge 35 :can

abut edge 17 andcooperate for slidable movement of the arm 11. along thehypotenuse edge 17Jof the triangle 10, while the straight edge 12 v.willalways be parallel with the base of said triangle 10.

' T-he'upper: corner of hypotenuse edge 17 of'the triangle; and thelower corner of the.,edge;35lof the "arm, are

slightly rounded 'along 'the vfull length ofeachto allow 'for:clear.passagerwhen :the arm 11Jisswung opento lay flat on the same planewiththe triangle :10; thus allowing clearance .for said edges lTand3-5'to abut properly.

On thetop face of the 45 degree right angle triangle 10, "aflatand-raised parallel. edged member serving asv a spacer36 isprovided. Said spacer 36 Tuns'parallel with and adjacent edge -22.thatis perpendicular to the base of said triangle. Spacer 36 :is'permanently attached to the top faceof the triangle, with'the. lower end'ofsame tapering to a wider, .width, and integrally formingthe rabbetedstrike 24. Spacer 36*.fills the space between the top face o-f'thetrianglef =10 and a portion of the top face of the arm 11, near thestraight edge: 12 for-said arm to lay flat andeven when:the attachmentis. in a closed position, such as shown in FIGURE .1.

Another spacer 37 serving as a stop,'is provided. The top face of saidspacer 37 is onthesame plane as the top face of the spacer 36. Spacer37' is permanently attachedtothe top face ofv theatriangle *10, andlocated under a small portion of the face of the arm 11, .near

the triangle is the longer the arm-of the attachment can be, inproportion to thesize of the triangle.

The above described straight edge attachment to con-;

ventional 45 degree'right angle drafting triangles is for aprecision-made; drafting instrument. There is provided according to'myinvention a more simple design working on the sameprinciple as theattachment described in connection with FIGURES "1, 2 and 3. This isdescribed;

herein following, and is shown .inFIGURE 4.

The 45 degree right angle triangle lllpartly shown in FIGURE ,4 is formeans of conserving space and. designated by the numeral 44, with oneend of the hypotenuse edge 42 shown meeting part of=the edge 45 that isperpendicular to the base :of the triangle 44. r The opposite end of thehypotenuse edge, not shown, -is:to be visualized as equal to the edge;42" asvshown, but opposite hand.

Themodificationof'this invention'comprises an arm 39 similar to the arm11 as describledinconnection .with

FIGURES I, 2 and 3. Said arm)39 has a straight edge.

40 meeting the. edge ,41'at a 45 degree angle, but having no lip 2*5.asdescribedimconnection with FIGURES 1, 2 and 3. The edge 41 tapers to aWider width, from the body of the narrower. parallel edged and extendedpart of the arm 39,-thus, aifording more edge surface for the edge '41to abutand slide against'the hypotenuse edge 42 of the triangle:

The modified-form'of the invention,.- used in conjunctionwitha-conventional 45 degree right angle triangle, is removable and is alsoprovided with a bracket 43,'said bracket beingsecured-tothe topface ofthe arm =39, in asuitable manner as describedin connection withiFIG-URES "1, 2 and *3 for the bracketi14.; However, bracket 43 has adifferent form .of slidable and parallel movement along the :topfaoeyand: near the edge,.ofr the hypotenuse side of the trianglex44ii-One: end .of this bracket 43 also tapers to a wider width from thenarrower paralleljedged It .is obvious from the extended end, with theunderside of said tapered end riding over the top face and along thehypotenuse side of the triangle 44.

The flat underside of said tapered end of the bracket 43 is providedwith a lowered portion, integral thereon, to form a tongue 46 which runsthe full width of the tapered end of the bracket 43. Tongue 46 havingits long sides parallel, fits in an open slot 47 located midway betweenhypotenuse edge 42 and opposite edge 48 that forms part of thetriangular cut-out 49.

Thus slot 47 forms a parallel sided groove, running parallel with thehypotenuse edge 42, into which the tongue 46 can be inserted for thesides of said tongue to abut the parallel sides of said slot and retainthe attachment for slidable and parallel movement along the hypotenuseside of the triangle 44. Arm 39 is located on the underside of thebracket 43 so as to have the edge 41 abut the hypotenuse edge 42 tocooperate with the tongue 46 when said tongue is retained in the slot47. Said slot 47 terminates at both ends slightly short of the twoapices that form the hypotenuse side of the triangle 44, with the endsof said slot being cut at right angles to the long parallel sides ofsaid slot. The ends of said slot 47 act as a stop for the ends of thetongue 46. The bottom edges of the tongue 46 and the bottom edge 41 ofthe arm 39 are beveled slightly and evenly along their full lengths,thus providing easement of connection prior to the atachment being fullyengaged when the attachment is lowered onto the triangle 44. Theunderside of said tongue 46 is slightly above the underside of saidtriangle 44 when said tongue 46 is fully engaged in slot 47.

Bracket 43 has a pointer 50, integral with and forming part of thebracket 43. Pointer 50 cooperates with the scale lines 51, and functionson the same principle as described in connection with the pointer 26 ofFIGURES 1, 2 and 3.

Furthermore it will be noted that said attachment a is provided with afinger grip or handle 52, located and attached to the top side of thebracket 43. Handle 52 extends lengthwise or parallel with bracket 43,and is situated with one end of said handle over the tapered end of thebracket 43, and the opposite end of said handle extending a distancethat will be partially past the edge 41 of the arm 39. Arm 39 can be ofa longer length than arm 11 as described in connection with FIGURES 1, 2and 3, since arm 11 is limited as to length to fit on the top side ofthe triangle 10 as described in connection with FIGURES 1, 2 and 3.

While only preferred embodiments of the invention have been shown in theannexed drawings and described in the specifications above, it iscontemplated to cover any variations, changes and modifications as touse and parts of materials chosen for the purposes of the disclosure andas claimed herein, which do not constitute departures from the spiritand scope of the invention set forth in the appended claims.

What is claimed is:

1. A triangle having an attachment comprising a flat arm with top andbottom sides on the same plane corresponding with that of the triangle,a straight edge on said arm, adapted to extend from the hypotenuse ofthe triangle and be parallel with the base of the triangle said armbeing beveled at a 45 degree angle from the straight edge, and beingadapted to slide evenly against the edge of the hypotenuse, and meansfor retaining the said arm in a position for slidable and parallelmovement along the hypotenuse, said arm comprising a bracket with oneflat and parallel edged extended and thereof being mounted over the topface and parallel with the edge or said arm.

2. A triangle according to claim 1 in which there is provided a bearingsymmetrical in section along the width of said arm and adapted to permitsaid attachment to be closed against the vertical arm of the triangle.

3. A triangle according to claim 2 provided with bearing means attachedat opposed ends to the hypotenuse, a rod adapted to fit in said bearingmeans, a slidable member having an extendable arm adapted to be moved toany position along the hypotenuse, and spring tension means between oneof the bearings and the slidable member.

4. A 45 degree right angle drafting triangle comprising a flat armhaving both top and bottom sides, a straight edge on said arm extendingfrom the hypotenuse edge of said triangle parallel with the base of saidtriangle, an adjacent edge of said arm beveled at a 45 degree angle fromthe straight edge, to abut and slide evenly against the hypotenuse edgeof said triangle, means for retaining said arm in a position forslidable and parallel movement along the hypotenuse edge of saidtriangle.

5. A triangle according to claim 4 wherein said means is a brackethaving one flat and parellel edged extended end mounted over the topface and being parallel with said straight edge of said arm and being ofa narrower Width than said arm to leave a portion of the top face ofsaid arm visible along the straight edge, the other end .of said brackettapering to a wider width and extending past the hypotenuse of saidtriangle to be over the top face of said triangle, the extreme end ofsaid tapered end shaped, thereon forming a bearing, the flat tapered endriding over the hypotenuse side of said triangle and meeting the side ofsaid bearing, said bearing being symmetrical in section along the Widthof said flat tapered end in relation to the top and bottom sides of saidbracket, said bearing being centrally bored with the axis of saidhearing at a 45 degree angle to the straight edge and parallel with thehypotenuse edge of said triangle, the axis of said bore being locatedmidway between the hypotenuse edge of said triangle and the edgeopposite that forms part of the triangular cut-out, said bearing furtherhaving a continuous outside diameter, concentric with the diameter ofsaid bore, the fiat tapered en-d riding over the hypotenuse side of saidtriangle being provided with a pointer and forming part of the bracket,said pointer having an edge parallel with said straight edge, to rideover and cooperate with scale lines engraved on the top face and alongthe hypotenuse side of said triangle, a rod held in fixed position overthe top face of said triangle with the axis of said rod parallel withthe hypotenuse side of said triangle, said rod being inserted to fitevenly in the bore of said bearing, means for holding said rod in afixed position, flat flanges extending on a diametrical line from thesides of second bearings with said flanges extending around the closedends of said second bearings, the underside of said flanges resting onthe top face of said triangle to be near the apexes forming thehypotenuse side of said triangle, said flanges being provided with holesbored to meet corresponding holes bored through the triangle to receiverivets or screws for holding said second bearings in a fixed position onthe top side of said triangle.

6. A triangle according to 5 wherein said means being second bearingshaving the same outside diameter as said first bearings, said secondbearings having bores of the same diameter as said first bearing toreceive a sufiicient portion of the extreme ends of said rod to retainsaid rod, the bores stop on the inside of said second bearings to formclosed ends, with the flat ends of said rod to abut said stops in saidbores, flat flanges forming part of said second bearings extending [outon a diametrical line from the sides of said second bearings with saidflanges extending around the closed ends of said second bearings, theunderside of said flanges resting on the top face of said triangle to benear the apexes forming the hypotenuse side of said triangle, saidflanges being provided with holes bored to meet corresponding holesbored through the triangle to receive rivets or screws for holding saidsecond bearings in a fixed position on the top side of said triangle.

7. A triangle according to claim 6 having a paraliel sided open slotthrough and along the hypotenuse side of said triangle parallel with thehypotenuse edge of. said; triangle directly under said'rod, the upper.edges of the:

long parallel sides of said-slot being concave in profile along theirfull lengths, said concave sides having an arc radius equal to, theoutside radius of said first and second bearings, said isl-otterminating at both ends and being under and flush with the underside ofsaid second bearings, with the underside of said first bearing restingin said concave sides for slidable 'and parallel movement of said firstbearing in said concave sides, a flat member serving asra spacer havingitsilong end parallel edged and mounted onthe top face of. said triangletoube parallel. with and nearthe edge of said triangle thatisperpendicular to the. base of saidtriangle, the lower end of the flat,

and parallel edged spacer tapering to a wider Width finom the narrowerparallel edged=end, :said tapered end of said spacer being located nearthe base of said triang1e,tsaid V tapered. end of said spacer beingthicker than ;the narrower parallel edged end of said spacer, to form 'astrike and having a rabbeted edge on said strike to receivea lip formedon the free end of said arm, the first bearing 7 being mounted to pivoton said rod, said rarm being adapted to be swung over on the top face ofsaid triangle and said a straight edge of said armbeing parallel withthe edge of said triangle perpendicular to the base of said triangle,with said .lip on the free, end of said arm engagedin the rabbeted edgeof said strike,,a portion-of the top facet of said arm along saidstraight edge-thus resting on the: topw of said narrowerparallel edgedend of said spacer, a cornpression' spring located on saidnod betweenthe ends of spacer in a positionwto ,abut, the edge [Oi said bracket;

References. Cited by the Examiner UNITED STATESVPATENTS 264,341 9/1882Richards" 3394 639,125 12/1889 Winnett 33-94 842,585 1/1907 R'oss 33=981,208,662 12/1916 Roth 3394' 1,268,756 1 6/:1918

LEONARD FORMAN, PfimaryExaminer-r- ISSAC .LISANN, Examiner.

J. D'. BOOS,-Assistant Examiner.

. Nicole 33-95"

1. A TRIANGLE HAVING AN ATTACHMENT COMPRISING A FLAT ARM WITH TOP ANDBOTTOM SIDES ON THE SAME PLANE CORRESPONDING WITH THAT OF THE TRIANGLE,A STRAIGHT EDGE ON SAID ARM, ADAPTED TO EXTEND FROM THE HYPOTENUSE OFTHE TRIANGLE AND BE PARALLEL WITH THE BASE OF THE TRIANGLE SAID ARMBEING BEVELED AT A 45 DEGREE ANGLE FROM THE STRAIGHT EDGE, AND BEINGADAPTED TO SLIDE EVENLY AGAINST THE EDGE OF THE HYPOTENUSE, AND MEANSFOR RETAINING THE SAID ARM IN A POSITION FOR SLIDABLE AND PARALLELMOVEMENT ALONG THE HYPOTENUSE, SAID ARM COMPRISING A BRACKET WITH ONEFLAT AND PARALLEL EDGED EXTENDED AND THEREOF BEING MOUNTED OVER THE TOPFACE AND PARALLEL WITH THE EDGE OF SAID ARM.